Haven's Deep by TW Iain

It used to be called Haven. The company said it was a simple mining operation. They said it was safe.

They said a lot of things.

Now called Haven’s Deep, the company’s expanded base holds a secret — a potential gateway to the Ancients. To the Heralds it’s a doorway to salvation. To Kaiahive it’s a portal to destruction.

And to the crew — to Brice, Deva and the others — it’s one more thing to contend with. As Haven’s Deep draws them closer, they must fight to make the right decisions. And not only for their own lives. 

The fate of humanity hangs in the balance.

Haven's Deep is the fourth book in the sci-fi action/adventure series ShadowTech.